Assessment of Optic Nerve Radiation in Patients With Glaucoma and Ocular Hypertension by 7 Tesla Diffusion Tensor Imaging

Summary

Glaucoma is among the leading causes for blindness in the western world. Elevated intraocular pressure (IOP) has been identified as the most important risk factor. However, some patients progress despite adequate IOP lowering while some subjects with elevated IOP never develop glaucoma. Other patients develop glaucoma although IOP measurements were always in the normal range. Therefore, other factors must be involved. In the last years, studies using MRI have been performed and evidence has accumulated that also changes in retrobulbar structures are present, in particular in the lateral geniculate nucleus and the visual cortex. However, these studies were limited by the low spatial resolution of the MRI instruments used.

The investigators propose to overcome this problem by using an ultrahigh-field Magnetom 7T whole-body MR scanner (Siemens Medical, Germany) installed at the MR Centre of Excellence at the Medical University of Vienna. This scanner is equipped with a 32-channel head coil and the SC72 high-performance gradient system and is thus perfectly suited for structural and functional imaging. The aim of the present study is to investigate whether structural and functional parameters are altered in patients with primary open angle glaucoma (POAG), normal tension glaucoma (NTG), ocular hypertension (OHT) compared to healthy control subjects. The exact topographical survey of intracranial structures such as the LGN and the assessment of neuronal structures by DTI may allow for the better assessment of therapeutic responses to new neuroprotective agents.

Conditions

• Primary Open Angle Glaucoma
• Ocular Hypertension
• Normal Tension Glaucoma

Interventions

DEVICE

7-Tesla MRI

High resolution functional and structural imaging of the visual pathway

OTHER

Optical Coherence Tomography

Measurement of retinal nerve fiber thickness

OTHER

Heidelberg Retina Tomography

Measurement of retinal nerve fiber thickness

OTHER

Scanning Laser Polarimetry

Measurement of retinal nerve fiber thickness

OTHER

Humphrey Perimetry

Visual Field Testing

OTHER

Applanation Tonometry

Measurement of Intraocular Pressure

Sponsors & Collaborators

• Medical University of Vienna

  lead OTHER

Principal Investigators

• Gerhard Garhoefer, MD · Department of Clinical Pharmacology, Medical University of Vienna

Study Design

Allocation

NON_RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2015-11-30

Primary Completion

2015-12-31

Completion

2015-12-31

Countries

• Austria

Study Locations